Strong strain modulation on magneto-resistance of La^sub 0.85^Sr^sub 0.15^MnO^sub 3^ film via converse piezoelectric effect

The strong strain modulation of the magneto-resistance and electrical capacitance of the La0.85Sr0.15MnO3 film deposited on Si substrate is realized via the converse piezoelectric effect of 0.72 Pb(Mg1/3Nb2/3)O3-0.28PbTiO3 (PMN-PT) single crystal adhered on the thin Si substrate together. The modulation arises from the induced lattice strain in the La0.85Sr0.15MnO3 film, which is induced by the electric-field-induced strain in the piezoelectric crystal. When an external electric field is applied to the PMN-PT layer, the electric-field-induced strain of the piezoelectric crystal will impose a compression strain on the film, subsequently resulting in an increase of the electrical resistance and electrical capacitance of the film. Under an electric field of ∼1 kV/cm, the electrical resistance of the film is enhanced ∼12.48% when the magnetic field is fixed on 0.2 T. The modulation mechanism which originates from the converse piezoelectric effect of piezoelectric material would be further extended to study the intrinsic strain of other oxide films.